diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index ed5cb5af52816940d45c6610e3e2e0d8c1d60a82..6b99fc3f9b6380f529ea5e65737194b079d47044 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -91,6 +91,7 @@ config S390 select HAVE_ARCH_MUTEX_CPU_RELAX select HAVE_ARCH_JUMP_LABEL if !MARCH_G5 select HAVE_RCU_TABLE_FREE if SMP + select ARCH_SAVE_PAGE_KEYS if HIBERNATION select ARCH_INLINE_SPIN_TRYLOCK select ARCH_INLINE_SPIN_TRYLOCK_BH select ARCH_INLINE_SPIN_LOCK diff --git a/arch/s390/kernel/suspend.c b/arch/s390/kernel/suspend.c index cf9e5c6d55274ce2da221e5f258fab08c58ee21e..b6f9afed74ec8e3c7e1082c82185e491b8b213aa 100644 --- a/arch/s390/kernel/suspend.c +++ b/arch/s390/kernel/suspend.c @@ -7,6 +7,7 @@ */ #include +#include #include /* @@ -14,6 +15,123 @@ */ extern const void __nosave_begin, __nosave_end; +/* + * The restore of the saved pages in an hibernation image will set + * the change and referenced bits in the storage key for each page. + * Overindication of the referenced bits after an hibernation cycle + * does not cause any harm but the overindication of the change bits + * would cause trouble. + * Use the ARCH_SAVE_PAGE_KEYS hooks to save the storage key of each + * page to the most significant byte of the associated page frame + * number in the hibernation image. + */ + +/* + * Key storage is allocated as a linked list of pages. + * The size of the keys array is (PAGE_SIZE - sizeof(long)) + */ +struct page_key_data { + struct page_key_data *next; + unsigned char data[]; +}; + +#define PAGE_KEY_DATA_SIZE (PAGE_SIZE - sizeof(struct page_key_data *)) + +static struct page_key_data *page_key_data; +static struct page_key_data *page_key_rp, *page_key_wp; +static unsigned long page_key_rx, page_key_wx; + +/* + * For each page in the hibernation image one additional byte is + * stored in the most significant byte of the page frame number. + * On suspend no additional memory is required but on resume the + * keys need to be memorized until the page data has been restored. + * Only then can the storage keys be set to their old state. + */ +unsigned long page_key_additional_pages(unsigned long pages) +{ + return DIV_ROUND_UP(pages, PAGE_KEY_DATA_SIZE); +} + +/* + * Free page_key_data list of arrays. + */ +void page_key_free(void) +{ + struct page_key_data *pkd; + + while (page_key_data) { + pkd = page_key_data; + page_key_data = pkd->next; + free_page((unsigned long) pkd); + } +} + +/* + * Allocate page_key_data list of arrays with enough room to store + * one byte for each page in the hibernation image. + */ +int page_key_alloc(unsigned long pages) +{ + struct page_key_data *pk; + unsigned long size; + + size = DIV_ROUND_UP(pages, PAGE_KEY_DATA_SIZE); + while (size--) { + pk = (struct page_key_data *) get_zeroed_page(GFP_KERNEL); + if (!pk) { + page_key_free(); + return -ENOMEM; + } + pk->next = page_key_data; + page_key_data = pk; + } + page_key_rp = page_key_wp = page_key_data; + page_key_rx = page_key_wx = 0; + return 0; +} + +/* + * Save the storage key into the upper 8 bits of the page frame number. + */ +void page_key_read(unsigned long *pfn) +{ + unsigned long addr; + + addr = (unsigned long) page_address(pfn_to_page(*pfn)); + *(unsigned char *) pfn = (unsigned char) page_get_storage_key(addr); +} + +/* + * Extract the storage key from the upper 8 bits of the page frame number + * and store it in the page_key_data list of arrays. + */ +void page_key_memorize(unsigned long *pfn) +{ + page_key_wp->data[page_key_wx] = *(unsigned char *) pfn; + *(unsigned char *) pfn = 0; + if (++page_key_wx < PAGE_KEY_DATA_SIZE) + return; + page_key_wp = page_key_wp->next; + page_key_wx = 0; +} + +/* + * Get the next key from the page_key_data list of arrays and set the + * storage key of the page referred by @address. If @address refers to + * a "safe" page the swsusp_arch_resume code will transfer the storage + * key from the buffer page to the original page. + */ +void page_key_write(void *address) +{ + page_set_storage_key((unsigned long) address, + page_key_rp->data[page_key_rx], 0); + if (++page_key_rx >= PAGE_KEY_DATA_SIZE) + return; + page_key_rp = page_key_rp->next; + page_key_rx = 0; +} + int pfn_is_nosave(unsigned long pfn) { unsigned long nosave_begin_pfn = PFN_DOWN(__pa(&__nosave_begin)); diff --git a/arch/s390/kernel/swsusp_asm64.S b/arch/s390/kernel/swsusp_asm64.S index 51bcdb50a23011a520afb29b092cc8aa871d1c80..acb78cdee896c1b9fe9c2d74ce212b254044a461 100644 --- a/arch/s390/kernel/swsusp_asm64.S +++ b/arch/s390/kernel/swsusp_asm64.S @@ -136,11 +136,14 @@ ENTRY(swsusp_arch_resume) 0: lg %r2,8(%r1) lg %r4,0(%r1) + iske %r0,%r4 lghi %r3,PAGE_SIZE lghi %r5,PAGE_SIZE 1: mvcle %r2,%r4,0 jo 1b + lg %r2,8(%r1) + sske %r0,%r2 lg %r1,16(%r1) ltgr %r1,%r1 jnz 0b diff --git a/include/linux/suspend.h b/include/linux/suspend.h index 76f42e49b72deea43a190677822070bea4e53eb1..46f3548aef2d23368c4f655f7e3d9cd82fa79c94 100644 --- a/include/linux/suspend.h +++ b/include/linux/suspend.h @@ -386,4 +386,38 @@ static inline void unlock_system_sleep(void) } #endif +#ifdef CONFIG_ARCH_SAVE_PAGE_KEYS +/* + * The ARCH_SAVE_PAGE_KEYS functions can be used by an architecture + * to save/restore additional information to/from the array of page + * frame numbers in the hibernation image. For s390 this is used to + * save and restore the storage key for each page that is included + * in the hibernation image. + */ +unsigned long page_key_additional_pages(unsigned long pages); +int page_key_alloc(unsigned long pages); +void page_key_free(void); +void page_key_read(unsigned long *pfn); +void page_key_memorize(unsigned long *pfn); +void page_key_write(void *address); + +#else /* !CONFIG_ARCH_SAVE_PAGE_KEYS */ + +static inline unsigned long page_key_additional_pages(unsigned long pages) +{ + return 0; +} + +static inline int page_key_alloc(unsigned long pages) +{ + return 0; +} + +static inline void page_key_free(void) {} +static inline void page_key_read(unsigned long *pfn) {} +static inline void page_key_memorize(unsigned long *pfn) {} +static inline void page_key_write(void *address) {} + +#endif /* !CONFIG_ARCH_SAVE_PAGE_KEYS */ + #endif /* _LINUX_SUSPEND_H */ diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index 3744c594b19b18b779b8d1f8660788a1e0aeacbf..e01e6899592c6b43b3d983fc300d8f62cfc2cb4f 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -65,6 +65,9 @@ config HIBERNATION For more information take a look at . +config ARCH_SAVE_PAGE_KEYS + bool + config PM_STD_PARTITION string "Default resume partition" depends on HIBERNATION diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 06efa54f93d6686bfc2f218d92149ee56cf9e511..cbe2c14413927c665f25d778fb03fde84af73421 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -1339,6 +1339,9 @@ int hibernate_preallocate_memory(void) count += highmem; count -= totalreserve_pages; + /* Add number of pages required for page keys (s390 only). */ + size += page_key_additional_pages(saveable); + /* Compute the maximum number of saveable pages to leave in memory. */ max_size = (count - (size + PAGES_FOR_IO)) / 2 - 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE); @@ -1662,6 +1665,8 @@ pack_pfns(unsigned long *buf, struct memory_bitmap *bm) buf[j] = memory_bm_next_pfn(bm); if (unlikely(buf[j] == BM_END_OF_MAP)) break; + /* Save page key for data page (s390 only). */ + page_key_read(buf + j); } } @@ -1821,6 +1826,9 @@ static int unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm) if (unlikely(buf[j] == BM_END_OF_MAP)) break; + /* Extract and buffer page key for data page (s390 only). */ + page_key_memorize(buf + j); + if (memory_bm_pfn_present(bm, buf[j])) memory_bm_set_bit(bm, buf[j]); else @@ -2223,6 +2231,11 @@ int snapshot_write_next(struct snapshot_handle *handle) if (error) return error; + /* Allocate buffer for page keys. */ + error = page_key_alloc(nr_copy_pages); + if (error) + return error; + } else if (handle->cur <= nr_meta_pages + 1) { error = unpack_orig_pfns(buffer, ©_bm); if (error) @@ -2243,6 +2256,8 @@ int snapshot_write_next(struct snapshot_handle *handle) } } else { copy_last_highmem_page(); + /* Restore page key for data page (s390 only). */ + page_key_write(handle->buffer); handle->buffer = get_buffer(&orig_bm, &ca); if (IS_ERR(handle->buffer)) return PTR_ERR(handle->buffer); @@ -2264,6 +2279,9 @@ int snapshot_write_next(struct snapshot_handle *handle) void snapshot_write_finalize(struct snapshot_handle *handle) { copy_last_highmem_page(); + /* Restore page key for data page (s390 only). */ + page_key_write(handle->buffer); + page_key_free(); /* Free only if we have loaded the image entirely */ if (handle->cur > 1 && handle->cur > nr_meta_pages + nr_copy_pages) { memory_bm_free(&orig_bm, PG_UNSAFE_CLEAR);